CVE-2026-25556 MuPDF 1.23.0 through 1.27.0 Barcode Decoding Double Free
A double-free vulnerability in MuPDF's barcode decoding allows attackers to crash the application or potentially execute code via crafted input.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-25556?
CVE-2026-25556 is a medium-severity use after free vulnerability in Artifex Mupdf, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
MuPDF versions 1.23.0 through 1.27.0 contain a double-free vulnerability in fz_fill_pixmap_from_display_list() when an exception occurs during display list rendering. The function accepts a caller-owned fz_pixmap pointer but incorrectly drops the pixmap in its error handling path before rethrowing the exception. Callers (including the barcode decoding path in fz_decode_barcode_from_display_list) also drop the same pixmap in cleanup, resulting in a double-free that can corrupt the heap and crash the process. This issue affects applications that enable and use MuPDF barcode decoding and can be triggered by processing crafted input that causes a rendering-time error while decoding barcodes.
Weakness: CWE-415
Which versions are affected by CVE-2026-25556?
It affects 1 product.
Products include Artifex Mupdf.
How do I fix CVE-2026-25556?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-25556 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25556 exists.
Other vulnerabilities in Artifex Mupdf
Sources
Also known as DEBIAN-CVE-2026-25556, GHSA-39p9-g2pq-q8r7, UBUNTU-CVE-2026-25556.